/**
 * Copyright 2009 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * 	http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.xume.raob.annotations;

import static org.xume.raob.util.StringUtils.isNotEmpty;

import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.List;

import org.xume.raob.core.BuildStep;
import org.xume.raob.exceptions.ObjectBuilderConfigurationException;
import org.xume.raob.util.ReflectionUtils;

/**
 * @author Johan Siebens
 */
public class CallForEachBuildStepFactory implements BuildStepFactory<CallForEach> {

	private Method method;

	public BuildStep[] getBuildSteps(Object... args) {
		List<Object> list = Arrays.asList((Object[]) args[0]);
		BuildStep[] result = new BuildStep[list.size()];
		int i = 0;
		for (Object object : list) {
			result[i++] = new BuildStep(method, new Object[] { object });
		}
		return result;
	}

	public void initialize(CallForEach callForEach, Method builderMethod, Class<?> targetClass) {
		Class<?>[] parameterTypes = builderMethod.getParameterTypes();
		if (parameterTypes.length != 1) {
			throw new ObjectBuilderConfigurationException("CallForEach methods should have exactly 1 parameter");
		} else if (!parameterTypes[0].isArray()) {
			throw new ObjectBuilderConfigurationException("CallForEach methods should have an array parameter");
		}

		Class<?>[] actualParameterTypes = { parameterTypes[0].getComponentType() };
		String methodName = defineMethodName(callForEach, builderMethod);
		this.method = ReflectionUtils.findMethod(targetClass, methodName, actualParameterTypes);
	}

	private String defineMethodName(CallForEach callForEach, Method method) {
		return isNotEmpty(callForEach.value()) ? callForEach.value() : method.getName();
	}

}
